One thing I noticed in Montreal is that when people go out to eat, they usually take their time and stay for a couple hours or more. Service will seem slow. Even at the cafes and pubs, don't go to dinner at 7:30 for a 9pm movie. They're not being rude to you because you're American, they just like to enjoy each others' company and digest their food. So enjoy being on vacation and stay a while. M2 also knows Montreal well and gave us a pretty good list of stuff to do when I took my wife. We went in the summer though. I haven't been up there for quite a while, but I've probably been to Canada 10 times in my life and ALWAYS had more trouble time-wise getting back into the Country.
Don't worry about ordering at McDonalds. Quarterpounder with cheese has same name in Canada.
Thanks for all of the advice! We ended up not going up there. The weather sort of got us. We originally planned to go December 23rd but got up to freezing rain and decided to put it off until the day after Christmas. We got up on the 26th and it was snowing pretty good in North Conway, NH. I checked the road conditions around the border and it said the road were partially ice and snow covered. And after considering I had drive through some high mountains to get over that way we decided not to go. I thought Canada will always be there and just have to go in the summer so weather won't be an issue.
But thanks again! RZ comes through as always when advice is needed.
Sorry to hear you didn't make it, but summer's the time to go anyway. Hope you can make that happen.